Recently, air bags have been applied in practical use as a safety device for the protection of the driver and passengers in a motor car. In general, such air bags are composed of a base fabric prepared by coating a nylon fabric with chloroprene rubber. There are weaknesses with the chloroprene coated fabric in that it is difficult to produce light-weight air bags using this fabric and the physical properties of it deteriorate with time. Recently, a proposal was made for a base fabric of air bags coated with silicone rubber in Japanese Kokai Patent Application No. Sho 63[1988]-78744. Although this base fabric for air bags coated with silicone rubber has excellent characteristics at high temperatures and its light weight is made possible by coating a thin membrane, the silicone rubber is insufficient in its adhesion to the base fabric, so that the base fabric coated with silicone rubber has the grave weakness of not being able to withstand impact with extension, especially extension at a high temperature. Furthermore, an emphasis has been placed on the property of an air bag being folded neatly for storage; fabric made of a polyamide fiber has become popular because of its excellent properties in this respect. However, it has become clear that severe curling occurs on the surface of this type of fabric for an air bag after silicone coating, making the sewing procedure difficult.
After intensive studies to solve the aforementioned problems, we discovered that a silicone rubber product containing an organohydrogen polysiloxane with a specific epoxy group adheres tightly to fabrics of a polyamide fiber or a polyester fiber and an excellent base fabric for an air bag could be produced by the polyamide fiber fabric or polyester fabric after coating and hardening using this silicone rubber product, without the aforementioned problem of curling. This invention is the result of the discovery.
The aim of this invention is to offer a base fabric for an air bag with excellent properties with respect to folding for storage and fabrication for sewing and adhesion strength to withstand the impact with extension, especially extension at a high temperature.